Health & Science

Pan: A bulge at the equator

Paleoanthropology Group MNCN-CSIC/AP, NASA, Alamy

Saturn’s ‘ravioli’ moon

A piece of ravioli? A hamburger? Tortellini, perhaps? A NASA spacecraft has gotten its best-ever look at one of Saturn’s moons— and its flying-saucer shape has drawn comparisons to all manner of foodstuffs. First discovered in 1990, the 21-mile-wide Pan orbits Saturn deep within the planet’s rings. Its striking appearance is the result of a bulge around its equator, which probably formed over time as the moon’s gravity attracted icy particles from the rings. Scientists believe the same process may have taken place on another of Saturn’s moons, Atlas, which has a similar equatorial bulge. The new high-resolution images—which were taken from about 15,000 miles away by Cassini, a probe that has been buzzing around Saturn for 13 years—should shed new light on Pan’s shape and geology. NASA’s Carolyn Porco admits she initially mistook the new photographs for an artist’s rendering. “They are real!” she tells NationalGeographic.com. “Science is better than fiction.” Saturn’s moons are potentially habitable— before Cassini runs out of fuel later this year, it will be sent deep into Saturn’s upper atmosphere so that it doesn’t crash into any of them.

Oceans warming faster

Scientists have developed more accurate ways to measure changes in Earth’s ocean temperatures—and they believe the seas are storing 13 percent more heat than previously thought. Since 2000, about 3,800 free-drifting “Argo” floats have been deployed throughout the world’s oceans, reports The Washington Post. These hightech devices, which profile conditions at depths of up to about 6,500 feet, have enabled researchers to improve assessments of ocean warming over the past 55 years. (Measurements were previously based solely on temperature readings recorded along major shipping routes.) In a new study that used data from the Argo system, government teams from the U.S. and China found that the seas are storing much more energy, in the form of heat—and that most of this change has occurred since 1980. Warming oceans affect weather patterns, triggering more powerful storms and flooding, and can lead to ocean acidification and “dead spots” inhospitable for marine life. Because the seas absorb more than 90 percent of the heat trapped in Earth’s atmosphere by greenhouse gases, says study co-author Kevin Trenberth of the National Center for Atmospheric Research, water temperatures are important barometers of global warming. “The ocean is the memory of all of the past climate change,” he said.

Vitamin C targets cancer

Most people take vitamin C to fend off a cold, but new research suggests it could also be a possible weapon in the fight against cancer. A team of researchers at the University of Salford in England evaluated seven substances— vitamin C, two natural products, and four experimental cancer drugs—on their ability to block the growth of cancer stem cells, which inhibit chemotherapy and help tumors spread throughout the body. They found that vitamin C did block the growth of cancer cells; in fact, it was 10 times more effective than one of the pharmaceuticals, although it was outperformed by two experimental drugs. The finding adds to previous research indicating that highdose vitamin C treatments could slow the growth of cancer cells in the prostate, liver, and colon. “Vitamin C is cheap, natural, nontoxic, and readily available,” study coauthor Michael Lisanti tells ScienceDaily.com. “To have it as a potential weapon in the fight against cancer would be a significant step.”

Health scare of the week

Gluten-free diets and diabetes

Gluten may have surpassed carbohydrates as public enemy No. 1, but new research suggests diets lacking in the protein could increase the risk for diabetes. Researchers at Harvard evaluated dietary surveys completed by about 200,000 people over three decades, reports ScienceDaily.com. They found that nearly 16,000 of those surveyed had developed type 2 diabetes—and that those who ate the most gluten had a 13 percent lower risk of developing the disease than those who ate the least. It’s unclear why gluten intake affects diabetes risk, but the study’s authors suggest people who eat glutinous grains—such as wheat, barley, and rye— also consume more fiber and other micronutrients, which could have a protective effect against the disease. Study author Geng Zong said the findings suggest that “people without celiac disease [should] reconsider limiting their gluten intake.”